Concentrations of stratospheric ozone have decreased significantly over the last two decades, resulting in detrimental impacts on humanity and the biosphere. In this presentation, Dr. Donald Wuebbles, professor at the University of Illinois, discusses the expectations for future levels of ozone, the attempts to prevent further effects on ozone, and the concerns that remain for ozone recovery. This lecture is part of the Walter Orr Roberts Public Lecture Series. Recorded on July 7, 2007 in Aspen, Colorado.